An imaging spectrometer employing tunable hyperchromatic microlenses

We present the design, fabrication and characterization of hydraulically-tunable hyperchromatic lenses for two-dimensional (2D) spectrally-resolved spectral imaging. These hyperchromatic lenses, consisting of a positive diffractive lens and a tunable concave lens, are designed to have a large longitudinal chromatic dispersion and thus axially separate the images of different wavelengths from each other. 2D objects of different wavelengths can consequently be imaged using the tunability of the lens system. Two hyperchromatic lens concepts are demonstrated and their spectral characteristics as well as their functionality in spectral imaging applications are shown

A transient analysis and characterization of latchup in bulk CMOS

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1983.MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERINGIncludes bibliographical references.by Hans Paul Zappe.M.S

Influencia de la mezcla forrajera y el manejo sobre el rendimiento y la composici?n bot?nica de dos praderas permanentes

Tesis (M. Sc) -- IICA, Turrialba (Costa Rica), 1965Se establecieron dos ensayos con praderas mixtas permanentes, dentro de terrenos pertenecientes al Centro de Investigaciones Agr?colas "Alberto Boerger", en La Estanzuela, Uruguay. El primero de ellos fue implantado en el oto?o de 1962, y tuvo por objeto estudiar el efecto de diferentes densidades de siembra de las especies utilizadas, sobre el rendimiento y la composici?n bot?nica de la pradera. Se emple? Festuca arundinacea, con cuatro densidades de siembra, asociada con una leguminosa sembrada a dos densidades. Las leguminosas fueron: Trifolium repens var. Ladino, Trifolium subterraneum y Lotus corniculatus. En el transcurso de los dos a?os de duraci?n del ensayo se practicaron 17 cortes, analiz?ndose separadamente la Producci?n de la gram?nea, la leguminosa y la Producci?n total. Se encontr? que las densidades de siembra de la festuca y la leguminosa influyeron sobre los rendimientos, pero que, a partir del corte 13, no hubo ya diferencias significativas. La especie de leguminosa influy? significativamente sobre la Producci?n a lo largo de este per?odo del ensayo. El tr?bol blanco m?s la gram?nea tuvieron una Producci?n total acumulada de materia verde de 99 toneladas por hect?rea, el tr?bol subterr?neo de 49 toneladas y el lotus de 58,5 toneladas. En la combinaci?n con tr?bol blanco se obtuvo la Producci?n m?s uniforme dentro de cada a?o. El segundo ensayo se sembr? en junio de 1963, emple?ndose una mezcla de Festuca arundinacea, Phalaris tuberosa, Trifolium repens var. Ladino y Lotus corniculatus. En este ensayo se intent? estudiar la influencia de diferentes combinaciones de pastoreo sobre la Producci?n total y la composici?n bot?nica de la pradera. Parecer?a que una carencia de nitr?geno en el suelo hizo predominar, ya desde el principio, al tr?bol blanco. Por ese motivo, no hubo cambios manifiestos en la composici?n bot?nica por efecto de los tratamientos. Estos en cambio influyeron fuertemente sobre la Producci?n total. En general, los pastoreos intensivos fueron m?s rendidores que los normales, pero los tratamientos normal todo el a?o e intensivo todo el a?o tuvieron la Producci?n acumulada m?s elevada, 70,5 y 73,7 toneladas de materia verde por hect?rea respectivamente, seguidos por el tratamiento normal en invierno, primavera y verano, e intensivo en oto?o con 66,7 toneladas. Un pastoreo frecuente e intensivo result? el m?s elevado en contenido porcentual de prote?na cruda. Como una conclusi?n general puede afirmarse que el manejo impuesto a una pradera influy? m?s sobre la Producci?n de forraje total que las densidades de siembra utilizadas

Understanding Photomechanical Behavior of Liquid Crystalline‐Based Actuators

Abstract Liquid crystalline‐based actuators containing azobenzene photoswitches have been used to demonstrate light‐responsive motion in soft actuator systems. Understanding the mechanical performance of these light‐responsive actuators as a function of the polymer chemistry as well as the nature and concentration of the photoswitches is crucial for developing advanced applications. A systematic study is presented here that clarifies the role of azobenzene photoswitches and the liquid crystalline networks in generating the desired photomechanical performance. Through measurement of photo stimulated mechanical behavior, in particular generated force and strain, a generalized set of guidelines concerning the appropriate subset of polymer chemistry and photoswitches required to achieve the desired performance for actuator design is derived

Tunable micro-optics

Presenting state-of-the-art research into the dynamic field of tunable micro-optics, this is the first book to provide a comprehensive survey covering a varied range of topics including novel materials, actuation concepts and new imaging systems in optics. Internationally renowned researchers present a diverse range of chapters on cutting-edge materials, devices and subsystems, including soft matter, artificial muscles, tunable lenses and apertures, photonic crystals, and complete tunable imagers. Special contributions also provide in-depth treatment of micro-optical characterisation, scanners, and the use of natural eye models as inspiration for new concepts in advanced optics. With applications extending from medical diagnosis to fibre telecommunications, Tunable Micro-optics equips readers with a solid understanding of the broader technical context through its interdisciplinary approach to the realisation of new types of optical systems. This is an essential resource for engineers in industry and academia, and advanced students working on optical systems design

Design of an all-liquid anamorphic imaging device

The design of a novel anamorphic optofluidic imaging system based on a pair of liquid lenses whose toroidal surfaces create different optical powers in the symmetry-axes is presented. Using electrowetting-ondieletrics for actuation, a cylindrical fluidic system is actuated by 32 azimuthally-distributed electrodes allowing the definition of non-rotationally-symmetric surface shapes. We present the design and simulation of this optical system and show that an anamorphic ratio of 1.43 at a maximum field of view of 6:82° is attainable